Gas range pilot light system



Aug. 29, 1961 B. MATTHEWS GAS RANGE PILOT LIGHT SYSTEM 8 4 3 7% l m o 40 .2 l m I w H C J 3 0 m 5 7 L R 5 H I I V IO l4 F rG.2

2,998,058 GAS RANGE PILOT LIGHT SYSTEM Birchard L. Matthews, Cleveland, Ohio, assignor, by mesne assignments, to Aurora Corporation of Illinois, a corporation of Illinois Filed Feb. 2, 1959, Ser. No. 790,414 8 Claims. (Cl. 158-115) This invention relates to gas ranges, and more particularly to improved pilot light arrangements and control mechanisms therefor in multiple burner type gas ranges.

For some years gas range pilot lighters of the Flash Lighter type have been in wide spread use; whereby a single pilot head is enabled to service a plurality of burners clustered around the pilot head. Such pilots however involve certain disadvantages, such as causing hot spots under parts of the gas range cover plate, and because in operation they were relatively slow in igniting the burners. Accordingly, low B.t.u. pilots have now been introduced, comprising separate pinhead size pilot jets logated adjacent each burner, thereby developing no appreciable heat concentrations under the range top plate while at the same time providing more instantaneous ignition due to the close proxirnities of the pilot jets to the burners. The introduction of such multiple, small size flash pilot arrangements involved however a new problem, and that is provision of means for readily and precisely adjusting the gas flow rates to the lighters separately. This has been found to be necessary to compensate for different length conduits running to the lighters, and other manufacturing inequalities; and because of the minute ness of the pilot jets of this type it is critical that precisely correct gas supplies be furnished them.

One of the objects of the present invention is to provide an improved pilot valve that can simultaneously control a plurality of pilot flames to deliver equal quantities of gas thereto with a high degree of accuracy.

Another object is to provide an improved integral assembly of multiple pilots and pilot control means, that can readily be installed as a unit in the top of a gas range.

It is another object of the present invention to provide an improved multiple burner pilot light arrangement and fuel supply system having a common pilot gas supply.

Another object is to provide in a system as aforesaid an improved multiple port, adjustable, pilot fuel flow control valve.

Still another object of the invention is to provide a multiple port pilot fuel flow control valve as aforesaid of a minimum number of inexpensively made parts, which is invariably operable to deliver gas through the various ports thereof at precisely equal rates.

Other objects and advantages of the invention will appear from the specification hereinafter wherein:

FIG. 1 is a plan view of a four burner pilot light arrangement and pilot fuel supply system of the present invention;

FIG. 2 is a fragmentary vertical view, on enlarged scale, through one of the pilot fuel control valves taken for example along line II-II of FIG. 1;

FIG. 3 is an enlarged fragmentary view of a portion of FIG. 2;

FIG. 4 is a view corresponding to FIG. 3, but of an alternative form of the flow adjustment device;

FIG. 5 is an end View of one form of pilot hood and jet component such as may be used in FIG. 1;

FIG. 6 is a view corresponding to FIG. 5, but of an alternative form of pilot hood; and

FIG. 7 is a view corresponding to FIG. 4, but of the modification shown in FIGS. 2-3.

As shown in the drawing herewith the invention may be embodied by way of example in a four burner gas range, whereby four identical pilot jets 10 are required, each being preferably encompassed by a draft hood 12. As shown in FIG. 5, the draft hoods may be of open bottom, open end, mail box form; or, as shown in FIG. 6 they may be of open end tubular form or of any other preferred style. The fuel feed conduits leading to the jets 10 are designated 14 and the gas supply conduit for the entire system is indicated at 15.

As shown in FIG. 1 the pilots are coupled in pairs through their feed conduits 14 to adjustable gas flow control valves 16; each valve 16 having a gas inlet port coupled to a supply conduit 18. The supply conduits 18-18 in turn connect to a pilot gas supply filter device 20 into which the supply conduit 15 delivers gas at line pressure. As illustrated in the drawing, the pilot jets 10 are preferably of hypodermic needle type.

It has been determined that in systems of this type, due for example to the differences in length of the conduits 18, 18, the jet feed conduits leading therefrom will receive gas under different pressures unless arrangements are provided for precise regulation of gas flows thereinto such as by means of the valves such as are indicated at 16, 16. Furthermore, it has been determined that the gas flow adjustment devices interiorly of the valves 16, 16 must be of special construction in order to insure delivery of gas from all of their outlet ports at equal pressures and rates.

Thus, for example as shown in FIGS. 2, 3, each valve 16 may comprise a vertically bored body into the lower end of which connects the gas supply conduit 18. A plurality of outlet port nipples 3030 are formed to extend radially from the body 16 for connection to the gas feed conduits 14- 14; the nipples 3030 being bored as indicated at 32 to communicate with the central bore of the valve body. To control the rate of flow of gas through the bores 32 piston means such as adjustment screw 35 is provided in the upper end portion of the body bore. An integrally formed cylindrical skirt portion 36 extends from the body of the screw in snug fitting relation with the bore so as to progressively throttle off the ports 32 as the screw 35 is rotated into the casing 16. The skirt arrangement is preferred because it facilitates provision at all times of a gas-tight seal between the outlet ports 32 and the relatively loose fitting threads of the screw 35, and also provides when the valve is in closed position a gas-tight seal with the side wall of the gas inlet main bore. Thus, it will be appreciated that opposite rotations of the screw 35 will variablythrottle the entrances of the bores 32 so that upon installation of the system the valves thereof may be readily adjusted to provide equal gas flows to all pilots notwithstanding the use of different length conduits at 1818 or other installation inequalities.

However, it has been determined that when operating with reduced gas flow rates through the ports 32 such as are required for economy reasons under standby or pilot idling conditions, the slightest manufacturing inaccuracies of the parts of the system such as are usually experienced, tend to cause intolerable imbalances of gas pressures and flow rates between the various outlet ports of the valves. For example, minuscule differences in the longitudinal positions of the entrances of the ports 32 into the valve bore will result in dilferential throttling thereof by the screw skirt 36. To insure against resultant unequal delivery of gas to the pilot jets of each valve group, a groove as indicated at 38 (FIGS. 2, 3) may be formed in the wall of the valve bore at an elevation slightly above but intercommunicating with both of the bores 32, 32. It will be appreciated that by virtue of this arrangemen t, if the skint portion 36 of the adjustment screw fully closes one of the ports 32 before closing the other ports of the valve, the gas entering the still open port or P 11 will not only flow to the associated jet but will also flow around in the groove 38 to thereby gain equal access to thc 'other ports and their associated jets. (FIG. 7)

Thus, equalized control of all pilot jets supplied 'by the single valve is assured despite any inaccuracies of the parts such asmay be encountered in the manufacture and assembly thereof. Alternatively, the gas flow equalizing groove may be provided in the outer surface of the skirt 36 of the screw 35, as indicated at 40 (FIG. 4). Also, it will of course be appreciated that although only one form of the invention has been shown and described in detail, it be apparent to those skilled in the art that the invention is not so limited but that various changes may be made therein without departing from the spirit of the invention or the scope of the appended claims.

I claim:

l. A multiple burner gas range pilot light system comprising in combination, a pilot gas supply conduit, a pilot light control valve connected to said supply conduit, said valve comprising a body having a central bore receiving gas at one end from tthe supply conduit, a plurality of gas passageways extending radially from said bore at a substantially common longitudinal position therein, an adjustment screw-threaded into the opposite end of said bore and having a cylindrical skirt portion snugly fitting said bore and being positionally displaceable longitudinally therein upon rotation of said screw whereby the rim of said screw is positionally adjustable to cause said skirt portion to variably throttle the entrances of said passageways into said bore, groove means running circumferentially around said skirt portion whereby to provide a gas passageway intercommunicating said bore with all of said passageway entrances whenever said skirt portion is in a position of opening at least one of said entrances, pilot feed conduits connecting to extend from each of said passageways, pilot flame jets connected to the ends of said feed conduits, and draft hoods substantially enclosing said jets.

2. A multiple burner gas range pilot light system comprising in combination, a pilot gas supply conduit, a pilot light control valve connected to said supply conduit, said valve comprising a body having a central bore receiving gas at one end from the supply conduit, a plurality of gas passageways extending radially from said bore at a substantially common longitudinal position therein, an adjustment screw'threaded into the opposite end of said bore and having a cylindrical skirt portion snugly fitting said bore and being position-ally displaceable longitudinally therein upon rotation of said screw whereby the rim portion'of said screw is positionally adjustable to cause said skirt portion to variably throttle the entrances of said passageways into said bore, groove means running circumferentially around said bore whereby to pro vide a gas passageway intercommunicating said bore with all of said passageway entrances whenever said skirt portion is in a position of opening at least one of said ontrances, pilot feed conduits connecting to extend from each of said passageways, and pilot flame jets connected to the ends of said feed conduits.

3. A multiple burner gas range pilot light system comprising in combination, a gas supply having a plurality of outlet ports, each of said outlet ports having a gas supply conduit connected thereto, said supply conduits being of different gas transmission coeflicient characteristics, a pilot light control valve connected to each of said supply conduits, each of said valves including a gas inlet bore and a plurality of outlet passageways communicating therewith, an adjustable screw displacea-ble to progressively throttle said outlet passageways, means providing a gas hy-pass passageway intercommunicating said bore with all of said outlet passageways whenever said screw is in a position of opening at least one of said passageways, pilot feed conduits connecting to extend from each of said passageways to pilot flame jets connected to the ends of said feed conduits.

4. A gas supply valve having a plurality of gas passageways extending radially from said valve, an adjustment screw threaded into said valve, and being positionally displaceable upon rotation of said screw whereby said screw is positionally adjustable to variably and progressively throttle the entrances of said passageways into said valve, and means providing a gas inlet passageway intercommunicating with all of said passageway entrances whenever said screw is in a position of opening not all of but at least one of said entrances.

5. A multiple burner gas range pilot light system, as defined in and by claim 3, wherein the said means that provides the by-pass passageway is an annular groove.

6. A multiple burner gas range pilot light system comprising in combination, a gas supply having a plurality of outlet ports, each of said outlet ports having a gas supply conduit connected thereto, said supply conduits being of diiferent gas transmission coefficient characteristics, a pilot light control valve connected to each of said supply conduits, each of said valves including a gas inlet bore and a plurality of outlet passageways communicating therewith, an adjustable valve means displaceable to progressively throttle said outlet passage ways, means providing a gas by-pass passageway intercommunicating said bore with all of said outlet passageways whenever said screw is in a position of opening at least one of said passageways, and pilot feed conduits connecting to extend from each of said passageways to pilot flame jets connected to the ends of said feed conduits.

7. A multiple burner gas range pilot light system as defined in claim 6, wherein an annular groove is in one of said means and provides the gas by-pass passageway.

8. A gas control valve comprising a body having a single gas inlet bore and a plurality of gas outlet passageways extending radially from said inlet bore, and a piston mounted in said body opposite said bore, said piston movable into said bore and out of said bore so as to control the flow of gas from said here into said passageways, said piston having an annular groove adjacent the end thereof and being substantially in register with said passageways when the end of said piston enters said inlet bore and of such depth and dimension so that in crements of the flow of gas will be distributed to each of said outlet passageways until the flow of gas to each of said passageways is shut oil? substantially simultaneously by said piston.

References Cited in the file of this patent UNITED STATES PATENTS 1,162,315 Southworth Nov. 30, 1915 1,929,088 Wood Oct. 3, 1933 2,094,284- Te Pas Sept. 28, 1937 2,664,153 Swenson et a1. Dec. 29, 1953 2,881,829 Matthews et a1. Apr. 14, 1959 

